Mods for robotic VX

[mbeach]

I'm assuming that this project is on some sort of budget.

I'd pick something not horribly expensive -your money would be better spent in software rather than tires. Having spent a fair bit of time driving about the Mojave Desert, I'd have to echo AlaskaVX's comment about flotation -fatter the better. The MT Bajas are reasonably priced, and offer excellent sand traction. Your speed(s) and route will not likely take you across tire-puncturing terrain, so just steer clear of any brush and mountains and your tires should be fine. You can add a can of Fix-A-Flat to each one to give you piece of mind.

Your robot's biggest enemies will be heat and vibration. Heat can be beat with a fair amount of A/C, but the VX is a well-known rump-shaker. Since plush suspensions aren't my thing, I'll have to hand that one off.

[Dallas4u]

Don't count out the Yokohama Geolander AT+II's!!!

[StinkBug]

i know the tire of choice for all the desert racer guys is the BFG Baja T/A, very tough, good in the desert, but also fairly expensive and somewhat stiff for some vehicles. Good luck.

Dallas

[Moncha]

http://www.austinrobot.com/

[WyrreJ]

That's odd. There was a press release a month or two ago from DARPA that listed all of the groups that made the first cut and I specifically looked for these guys and did not find them on the list. After that, I stopped paying attention.

[Jorge]

That's odd. There was a press release a month or two ago from DARPA that listed all of the groups that made the first cut and I specifically looked for these guys and did not find them on the list.

Hello WyrreJ,

NOTE: Wow... this ended up being a longer post than I thought when I started writing it... Sorry for the long post :-)

DARPA originally intended to invite 40 teams to the National Qualification Event (NQE) to be held at the California Speedway September 28 through October 5th. The original cut of 40 teams were selected after the results of the first site visit (DARPA representatives visited more than 100 teams). During our first site visit back in May, our robot successfully avoided the random obstacles (plastic trashcans) placed by DARPA along the test track.

Unfortunately (due to technical glitches and due to the fact that this is an INCREDIBLY hard problem ;-) Our robot did the runs only at idle speed (and DARPA wants a *fast* robot). We therefore did not make the first cut of 40 teams... but DARPA realized there were several really good teams that were left out, so they bent the rules a bit (they are the DoD, and they *make* the rules, so they can bend them if they want :-) Basically DARPA decided to select the top nine teams who did not qualify and award them "alternate" status. The original intent was to use the alternate teams to fill any spots if one of the top 40 teams had to drop out of the race. The ranking of the "alternate" teams would be used to determine which teams would get invited first. Back in June DARPA scheduled a second site visit for all the alternate teams and DARPA announced that they *may* invite the top 3 teams to participate at the NQE depending on the results of the 2nd site vist. Here is a link to the DARPA press release:

http://www.darpa.mil/grandchallenge/...nal_July_5.pdf

So for the past 3 months we have been kind of like an NFL Wildcard team :-) I guess it was not too bad making it to the same list a Princeton University ;-)

Two weeks ago DARPA came and visited our robot again, and we were fortunately selected as one of the top 3 teams. As a matter of fact, the top three alternate teams had a strong enough showing that DARPA invited them (us) to the NQE as actual bona-fide semi-finalists:

http://www.darpa.mil/grandchallenge/...ss_Release.pdf

We are no longer an alternate team... we will compete on the same footing and on equal ground as the rest of the 40 teams selected in June. So at the end of September you will see our team at the California Speedway, competing against the big boys :-) MY GOSH!!! IS THAT REALLY LESS THAN FOUR WEEKS AWAY?!?!?!

Thanks for the interest... gotta run... I'm trying to figure out the max safe speed for the robot given the radius of curvature of upcoming curves :-)

Jorge

[Anita]

Hmm ... California Speedway

That is not too far from a lot of us L.A. VXers. Is it possible that we can meet up with you? I think that would be a very cool thing to do.

[Jorge]

Is it possible that we can meet up with you?

Hello Anita,

Our team is allowed 25 guest passes at the California Speedway. I can't make any promises yet because we have to make sure all our sponsors and family members get passes, but we may have a couple we can make available for a day. If you think you would like to make use of the guest passes, please keep in touch with me and I'll try to save some for you. The best way to reach me is to go to our website (www.austinrobot.com) and send me email via the "Contact Us" link.

Thanks,

Jorge

[Moncha]

Hmm ... California Speedway

That is not too far from a lot of us L.A. VXers. Is it possible that we can meet up with you? I think that would be a very cool thing to do.

Maybe I could work up a nice shirt for the event.. And you could be our rep?!?!

[GoIsuzu]

I'd go with laptops. TuffBooks for starters are designed for harsh operating environments and are probably tops when it comes to resisting damage caused by excessive vibration/impacts. From there I'd mount the laptops on anti-shock plates. A good home-made solution is to place a metal plate on top of a sealed bag of motor oil. The oil in the bag dampens vibration. The metal plate on top will sway/wave rather than vibrate.

I use an older Dell laptop as the "brains" of the DashPC/sound system in my Mits 3000GT and the suspension on it is pretty tight. Haven't had a problem with the computer so far.

So again, I'd definitely go with some laptops for your on-boards.

[Art]

A good home-made solution is to place a metal plate on top of a sealed bag of motor oil. The oil in the bag dampens vibration. The metal plate on top will sway/wave rather than vibrate.

We have chosen our computer systems, but not our shock isolation strategy. Thank you for your suggestion for shock plates. We will give that a try!

[Swordy]

Unless you are using an Ai type system, I think I'd skip the front locker. The steering is soo much different when the front is locked. It won't just go where you point it. Plus it may or may not imediately disengage when turned off. It sure would help get out of being stuck though. The solid state hard drives would be sweet too, but those are some pretty pricey little drives. Last time I checked a decent size one was like 4 to 5 grand. I guess it would cure about 95% of your vibration concerns though.

And yes, those are the correct ARB part numbers.

[Maugan_VX]

swordy: the lockers could be engaged while there is wheel spin present. I'd think they'd be smart enough to program the thing to get itself unstuck first, THEN get back on course.

I dunno, I'm pretty uneducated about the whole competition. It just seems logical for me to get out of a rough spot before concentrating on where I want to go. Of course the trick is to never get in the rough spots.... where do you start. I need more beer.

[megadan]

I don't want to sound like a downer, but your choice of vehicle for the DGC is largely irrelevant. It's not an off-road vehicle problem - it's a computer vision and mapping problem. I know, I was a software engineer on one of the original teams and spoke AT LENGTH to the DARPA people during the kick-off meeting at the Peterson Museum here in LA. We built a vehicle with dynamics that would pop the front windshield out of a VX at speed, so I am quite familiar with the development tree. And out weak point was software, not the "airframe."

80% of the 2nd gen teams out there thing they can solve this comp with a super off-road machine. What you need is some super software engineers in the areas of digital vision, path planning, fast control systems, etc. As a basic litmus test, if you can pretty much ignore GPS positioning in your Kalman filter, then you have a shot at getting into the course. (If you don't know what a Kalman is, then don't start cutting up your VX!)

Email me if you want, dan.danknick@gmail.com

Dan

PS: If you're just doing this for fun and don't have any serious intent of doing well, then ignore all of this and enjoy the ride!

[Maugan_VX]

How is a digital camera supposed to tell the difference between good traction and no traction?

I understand that it can identify obstacles, but sometimes you need all 4 wheels delivering power at once.

And if they wanted the ultimate offroad vehicle, I don't think they would have picked a VX.